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Fuel additives

At the risk of starting a huge row or rehashing  a topic that has been wrung out dry too many times: do the members here habitually add anything to the fuel for the M11/ISM engine? Cetane booster? Lubricant? Biocide? I have Powerstroke 6.0L and we add stuff to fuel and oil.
97 U320
Build 5099
Victoria, Tx

Re: Fuel additives

Reply #1 –
Two additive recommendations:

When storing diesel for over 2 months in the summer or 3 in winter, add a BIOCIDE and top off tank to reduce condensation.

When you may be using summer grade fuel (#2 diesel) in below freezing temperatures, add an anti-gel.

DONE.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Fuel additives

Reply #2 –
religiously add biocide - cheap insurance
Tim Fiedler    2025 LTV Unity MBL on Order
2000 Chevy Tracker 2 Door Convertible 4WD Now lifted 4.5"
1985 Citroen 2CV6 Charleston
Murphy Rebel on wheels with 175HP Titan
Cessna P337
1980 48' Westport MY (!/4 Share)

Re: Fuel additives

Reply #3 –
Quote from: Tim Fiedler –
religiously add biocide - cheap insurance
Yep biocide at every fill.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Fuel additives

Reply #4 –
Biobor shock dose here with some Penray for asphaltine, in an ISL.

Re: Fuel additives

Reply #5 –
I use:

1) Opti Lube XPD - Increases the lubricity. Doubles the storage life of diesel fuel.
2) Star Tron Enzyme Fuel Treatment - Super Concentrated Diesel Formula - Stabilize fuel for up to two years, preventing the formation of gums and other solids that clog fuel injectors.

In 16,000 miles, I had zero fuel issues.
1997 U270 34FT Build 5140 Cummins 8.3 Allison 3060R
Solar 1920Watts, 14KWH lithium. Orion BMS.

Re: Fuel additives

Reply #6 –
I toss in some cheap 2cycle oil once in a while. And some diesel clean if I feel like it.

I don't like to use biocide unless there is an issue.  And I've never had an issue...yet. Using the RV and burning fuel helps minimize the issues.
1998 U270 34'

Re: Fuel additives

Reply #7 –
We bought this thing in Jan of 17 and in these 30 months have put about 27k miles on it. So it seems unlikely that fuel stabilizers would be necassary for us.
97 U320
Build 5099
Victoria, Tx

Re: Fuel additives

Reply #8 –
I carry a gallon of Diesel Kleen next to the tank. In California, much of our diesel, especially in the smog prone valley, is either B5 or B20. Most everything is great except it can absorb more moisture compared to dino-diesel. I've had many customer cars pick up a load of algae and have gotten some myself so like the biocide occasionally. I use the Diesel Kleen additive more in cold weather as it raises the cetane rating allowing the diesel to explode at lower cylinder pressures so it starts better on cold mornings. So, if you worry about cold weather starting, use a cetane rating improver. Many times a diesel RV will have a tank of summer diesel and if operated in the colder months, it may not start as well until the winter blend has diluted the summer fuel.

What Cetane Value Does in Diesel Engines

Turbo diesels may have a lower compression ratio. For instance, a U300 with the 2-cycle Detroit does not start that well in cold weather while a fire truck with a Detroit may be an instant start in cold weather. So many mechanics have no clue to the reason and point their finger at wear from light use, poor owner maintenance, etc The real reason is the turbo engine has a compression ratio of 17 to 1 while the non turbo version has a 19 to 1 compression ratio. This makes all the difference in the world. Detroit generators are delivered with pistons for the best compression ratio for the altitude they are to be installed at. The higher the altitude, the higher the compression ratio.

I don't worry about long term diesel storage as my Case backhoe uses 15 year old diesel from our tank. It starts and runs the same with fresh or old fuel. Gasoline is another story. Most of our new cars had been sitting both at the dock or while underway on the ship for a month. With the EPA's three bag test that cost over $1000, the gas cars got injection cleaner as soon as we picked them up from customs. There was a very noticeable difference in the way they ran.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Fuel additives

Reply #9 –
Does diesel fuel stratify after sitting for a month, or would it take a year?
1997 U270 34FT Build 5140 Cummins 8.3 Allison 3060R
Solar 1920Watts, 14KWH lithium. Orion BMS.

Re: Fuel additives

Reply #10 –
I always add BioborJF if we will be parked for more than a few weeks. I've never heard of any reason not to use it.
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186

Re: Fuel additives

Reply #11 –
Opti-Lube (the brand Tim mentioned earlier) makes a whole line of snake oils (Oops - I mean additives).  I keep a 6-pack of the 8 ounce bottles of their Summer+ blend with us.  I add a bottle to the tank along with the last fill up before we get home from a trip.  That way, the magic stuff can do whatever it does while the coach sits in our driveway - waiting for our next outing.

I'm not convinced adding anything to diesel fuel is really necessary, at least where we live (Hot Dry TX).  But I figure it won't hurt anything either...
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Fuel additives

Reply #12 –
Quote from: Tim –
Does diesel fuel stratify after sitting for a month, or would it take a year?
Have never seen it stratify. We have a 500 gallon tank that was filled many years ago. Still 3/4 full. I know it has a little algae in it but I've got a filter on the valve at the bottom so never have a problem with anything getting in the tank on the Case, diesel generator or a car in an emergency. There are quite a few places where crude oil is a clear yellow color and other places where it's greenish. These could be burned out of the ground in ship diesels. Tar sand crude is junk with a ton of sulphur and other nasty stuff. So, you could say that some crude/diesel has been in the ground for millions of year and is still ready to fuel a big diesel. Probably thin it with a little gasoline and burn it in a RV diesel.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Fuel additives

Reply #13 –
What the other Brett said.  I have a basic aversion to putting cash in my fuel tank.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: Fuel additives

Reply #14 –
I appreciate that this thread was begun with the newer engine in question.  For my older C8.3 mechanical, I have been advised to add a lubricate for the fuel injector because of the changes in modern fuel.  Is this accurate or am I wasting money and effort to add this stuff?
Carolyn and Lewis (Andy1) Anderson
1996 U270 36'

Re: Fuel additives

Reply #15 –
Most stations these days sell fuel with a percentage of biodiesel and my understanding is that the biodiesel adds lubricity and therefore no additives (other than a biocide such as BioborJF) are needed.
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186
 

Re: Fuel additives

Reply #16 –
Quote from: Lewis Anderson –
I appreciate that this thread was begun with the newer engine in question.  For my older C8.3 mechanical, I have been advised to add a lubricate for the fuel injector because of the changes in modern fuel.  Is this accurate or am I wasting money and effort to add this stuff?
That's the advantage of bio-diesel. Better lubricity and lower emissions. Quote: Biodiesel has higher lubricity (it is more "slippery") than petroleum diesel. This is a good thing, as it can be expected to reduce engine wear. ... Biodiesel has a higher oxygen content (usually 10 to 12 percent) than petroleum diesel. This should result in lower pollution emissions. This should also include lower injection pump wear and less wear on the little pintle that is in constant motion inside each one of your 8.3's fuel injectors. The Ultra Low Sulphur Diesel (ULSD) <15 ppm is not as good a lubricant as the older fuel was. So yes, this is one of the reasons I use an additive.

To me, the money waste is polishing the fuel. Your fuel tank and fuel is only as clean as the last time you filled it. NASA clean is ruined the first time you get fuel with any contamination in it. The primary and secondary are designed to filter out any harmful particles/algae.

I use an additive with a cetane improver because it starts better in cold weather and up at altitude where we spend most of our time. An occasional use of a biocide will kill (but not remove) any algae living in the water/diesel interface. It can also loosen any deposits in the tank and fuel lines.

Even at $4 plus a gallon, diesel is cheap compared to Europe. Their higher price comes with many advantages, one being constant monitoring of service station tanks for contamination. This is the big reason it pays to carry extra filters here and know how to change them. Drive long enough and you WILL have a fuel contamination problem. Fuel is cleaner than it used to be but a long ways from perfect.

I fueled a diesel car while crossing the Mojave. A few miles later, the engine started making a clattering noise to the point that I slowed down to about 40 mph. I limped to the next truck stop and bought a quart of additive. I added it to the tank while the engine was running and in just over a minute, the noise totally went away. Sure made a believer out of me.

Since I frequently use very old diesel fuel in our tractor, this article is a good read and also for any RV operator. A bit gloom and doom but it shows the complex relationship between our engines and the fuel they burn. This is why I use an additive most of the time and a biocide occasionally. The article mentions 4 microns, a lot finer than our coaches use in the secondary filter. Also explains the reason to carry an extra filters and know how to change them. When I imported a lot of diesels in the 70s and 80s, the fuel was so bad that water would collect in the secondary filter and actually rust a hole in the bottom of the filter. Every diesel I imported got a 2 micron Racor filter with a couple of extra cartridge for the glove compartment. That totally stopped the fuel problems. It was amazing how quickly the 2 micron filter needed changing. Back in those days everyone wanted a Mercedes diesel and every soccer mom had to have their station wagon (300TD).

Real Story of Bad Diesel Fuel - Diesel Fuels

There is nothing as good as a Bosch inline piston injection pump (P pump). They will outlast a half dozen engines. If properly calibrated, a 600 RPM idle will be glass smooth in a 6 cylinder Cummins.

Pierce

Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)